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Python TCP sockets won't connect

As part of a uni course, I have to write a simple python TCP client-server chat but I'm having issues getting the sockets in the server.py and client.py programs to connect.
After many attempts I decided to really strip back the program to just try to connect the sockets and have the client send one message to the server after they are connected.
I am running the two programs (server.py and client.py) on the same computer (macOS) in separate terminal windows. I have tried turning off the firewall and running the programs as well just in case that was somehow causing an issue.
My code is as below:
server.py - This is run first
from socket import *
serverPort = 11500
serverSocket = socket(AF_INET, SOCK_STREAM)
serverSocket.bind(('', serverPort))
print("The server is listening")
serverSocket.listen(1)
clientSocket, clientAddress = serverSocket.accept()
message, clientAddress = serverSocket.recvfrom(2048)
client.py - Once server.py is running, this is then started
from socket import *
serverName = "127.0.0.1"
serverPort = 11500
clientSocket = socket(AF_INET, SOCK_STREAM)
clientSocket.connect((serverName, serverPort))
message = "Hello"
clientSocket.send(message.encode())
This is the error I have been receiving:
(base) me#ME python_socket % python3 tcp_server.py
The server is listening
Traceback (most recent call last):
File "tcp_server.py", line 11, in <module>
message, clientAddress = serverSocket.recvfrom(2048)
OSError: [Errno 57] Socket is not connected
Thanks in advance for any help. It seems like something that should be really simple but even after watching tutorials online I still seem to have the issue of the sockets not connecting.

Problems
You should use recv() instead of recvfrom() when you connect using TCP. recvfrom() is used for UDP socket.
Instead of receiving data from serverSocket, you should use newly created TCP clientSocket.
Correct Solution
Server
from socket import *
serverPort = 11500
serverSocket = socket(AF_INET, SOCK_STREAM)
serverSocket.bind(("localhost", serverPort))
print("The server is listening")
serverSocket.listen(1)
clientSocket, clientAddress = serverSocket.accept()
message = clientSocket.recv(2048).decode()
print(message)
Client
from socket import *
serverName = "127.0.0.1"
serverPort = 11500
clientSocket = socket(AF_INET, SOCK_STREAM)
clientSocket.connect((serverName, serverPort))
message = "Hello"
clientSocket.send(message.encode())
Server Output:
The server is listening
Hello

The issue is that, in the server.py code, you should replace serverSocket in the recvfrom line with clientSocket, since when you call accept right before that line, clientSocket (returned by accept) is a new socket specific to that connection.
clientSocket, clientAddress = serverSocket.accept()
message, clientAddress = clientSocket.recvfrom(2048)
After that change, it is going to work just fine.

How to setup Linux VM in azure so that we can make it as a server(not a apache web server) for socket programming

I Just install linux VM in azure cloud and created a server.py which basically receive data from client.py located at another host and returns capitalize form of data. When i run server.py in my vm its running and when i send data through client.py to the server.py i don't know wether the data transaction occurs or no wether connection is etablished or not, but nothing happens:
client.py:
enter code here
from socket import *
serverName = '13.91.90.71'
serverPort = 12000
clientSocket = socket(AF_INET,SOCK_DGRAM)
message = input('Enter lowercase sentence:')
clientSocket.sendto(message.encode(),(serverName, serverPort))
modifiedMessage, serverAddress = clientSocket.recvfrom(2048)
print (modifiedMessage.decode())
clientSocket.close()
server.py:
enter code here
from socket import *
serverPort =12000
serverSocket = socket(AF_INET, SOCK_DGRAM)
serverSocket.bind(('', serverPort))
print('Ready to listen')
while 1:
message,clientAddress = serverSocket.recvfrom(2048)
modifiedMessage = message.upper()
print(modifiedMessage)
serverSocket.sendto(modifiedMessage, clientAddress)

For your issue, the problem is that you need to change the bind of the server like this:
serverSocket.bind(('0.0.0.0', serverPort))
or
serverSocket.bind(('vm_private_ip', serverPort))
The vm_private_ip is the real IP address of the VM. And then you also need to add a rule to the NSG associated with the VM to allow the port 12000.

I am testing to see if the TCP Client and Server are communicating but upon running, the client side does nothing

I have an assignment where I have to write TCP client server python programs to implement a basic voting application. There are only two candidates: JohnD and JaneD. I was testing the communication between the client and server. So when I run the client side, nothing happens. Could someone tell me why.
At first I was using "localhost" for serverName but I kept getting this error: clientSocket.connect(("localhost", serverPort))
ConnectionRefusedError: [WinError 10061] No connection could be made because the target machine actively refused it
So I set the serverName to my local IP. The client runs but nothing happens.
#TCP CLIENT#
from socket import*
#serverName = "localhost"
serverName = "131.100.39.41"
serverPort = 9001
clientSocket = socket(AF_INET, SOCK_STREAM)
clientSocket.connect(("131.100.39.41", serverPort))
option = input("Enter the voter name: ")
clientSocket.send(bytes(option, "utf-8"))
print("Name sent to server.", option)
clientSocket.close()
This is the server side.
#TCP SERVER#
from socket import*
serverPort = 9001
serverSocket = socket(AF_INET, SOCK_STREAM)
serverSocket.bind(("", serverPort))
serverSocket.listen(1)
print("Server is up and running.")
while(1):
connectionSocket, addr = serverSocket.accept()
option = connectionSocket.recv(1024)
print("received from client", option)
serverSocket.close()

This code looks good. It is working.
You get connectionRefused error in client , because the PORT is not opened , or there is 2 channels opened for the port. The port is opened for listening only when the server is started.
check with 'netstat -anp | findstr ":9001"
If there is port already opened , then choose another port or kill the port.
Remember:
Change your socket back to localhost or 127.0.0.1
First Start the server and then start the client
below is output i recieved , when i ran your code
Server
Server is up and running.
received from client b'test'
client:
Enter the voter name: test
Name sent to server. test

ConnectionRefusedError: [Errno 61] Connection refused macOS High Sierra

In the first part of this assignment you are going to implement an echo server which receives text message from client and sends it back to the client. (That’s why we call it echo server) When the server receives the text message from client, it capitalizes the odd characters of the text message. For example, when the client sends a text message of “hello elec 4120 student”, the server should return a text message of “HeLlO ElEc 4120 StUdEnT”.
With some hints from the instructor, my server code is as follow
from socket import *
serverPort = 12000
#create TCP welcoming socket
serverSocket = socket(AF_INET,SOCK_STREAM)
serverSocket.bind(('',serverPort))
#server begins listening for incoming TCP requests
serverSocket.listen(1)
print('The server is ready to receive')
while True:
#server waits on accept()
#for incoming requests, new socket created on return
connectionSocket, addr = serverSocket.accept()
#read bytes from socket (but not address as in UDP)
sentence = connectionSocket.recv(1024).decode()
capitalizedSentence = sentence.upper()
#close connection to this client (but not welcoming socket)
connectionSocket.send(capitalizedSentence.encode())
connectionSocket.close()
and the client code is
from socket import *
serverPort = 12000
serverName = 'localhost'
#create TCP socket for server, remote port 12000
clientSocket = socket(AF_INET, SOCK_STREAM)
clientSocket.connect((serverName,serverPort))
sentence = raw_input('Input lowercase sentence:')
#No need to attach server name, port
clientSocket.send(sentence.encode())
modifiedSentence = clientSocket.recv(1024)
print ('From Server:', modifiedSentence.decode())
clientSocket.close()
and when I run the server code
'The server is ready to receive'
is shown but when I run the client part,
line 6, in <module>
clientSocket.connect((serverName,serverPort))
ConnectionRefusedError: [Errno 61] Connection refused
is shown

error: [Errno 10061] No connection could be made because the target machine actively refused it

I was building a simple client/server code and i keep getting this error. I dont understand why (I am trying to get used to python). here is my code:
Server Code:
import socket
from socket import*
from time import ctime
HOST = ''
PORT = 21567
BUFSIZ = 1024
ADDR =(HOST, PORT)
tcpsersock = socket(AF_INET, SOCK_STREAM)
tcpsersock.bind(ADDR)
tcpsersock.listen(5)
while True:
print("waiting for connection...")
tcpclisock, addr = tcpsersock.accpet()
print("...Connected from: "),addr
while True:
data = tcpclisock.recv(BUFSIZ)
if not data:
break
tcpclisock.send('[%s] %s' %(ctime(), data))
tcpclisock.close()
tcpsersock.close()
Client Code:
import socket
from socket import*
from time import ctime
HOST = 'localhost'
PORT = 21567
BUFSIZ = 1024
ADDR = (HOST, PORT)
tcpclisock = socket(AF_INET, SOCK_STREAM)
tcpclisock.connect(ADDR)
while True:
data = raw_input('> ')
if not data:
break
tcpclisock.send(data)
data = tcpclisock.recv(BUFSIZ)
if not data:
break
print data
tcpclisock.close()
I get this error:
error: [Errno 10061] No connection could be made because the target machine actively refused it

Try this:
tcpclisock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
This is almost straight from the documents page for socket which you can find here socket

Probably there is no server process running on the server side (due to accpet()?)

That suggests the remote machine has received your connection request, and send back a refusal (a RST packet). I don't think this is a case of the remote machine simply not having a process listening on that port (but i could be wrong!).
That sounds like a firewall problem. It could be a firewall on the remote machine, or a filter in the network in between, or, perhaps on your local machine - are you running any kind of security software locally?

first run the server script -- which starts listening
then open the client ..
or -- try to change the port
the error simply indicates "that no one is listening"